Fig. 2.

Effect of AlCl₃ on root elongation of Arabidopsis wild-type (Col-0) and ethylene-insensitive mutants, etr1-3 and ein2-1. (A) Seedlings of Col-0, etr1-3, and ein2-1 were exposed to 50 μM AlCl₃ and root elongation was measured under a stereomicroscope after exposure of seedlings for 24 h. (B) Effect of varying concentrations of AlCl₃ on root growth of seedlings grown on agar. Primary root length was measured before and after transferring wild-type seedlings to agar medium with varying concentrations of AlCl₃ (0, 50, 100, and 200 μM, pH 4.5) for 4 d. Data are expressed as root elongation relative to controls, and given as means ±SE of >8 roots. The root elongation rate in the absence of AlCl₃ for Col-0, etr1-3, and ein2-1 was 5.41±0.13 mm d⁻¹ (n=17), 6.06±0.59 mm d⁻¹ (n=6), and 6.66±0.66 mm d⁻¹ (n=6), respectively.